ABSTRACT
The emissions of ultrafine particles (UFP) depend on the formation as well as the performance of the flue gas cleaning system. Biomass boilers are typically equipped with bag filters and electrostatic precipitators, whereas waste-to-energy plants may have different types of systems. A total of five biomass plants fuelled with wood or straw, five waste-to-energy plants (municipal solid waste and light industrial waste), ten natural gas engines, two engines fuelled with biogas, and finally two natural-gas-fired turbines were included in the measuring campaign. The measurements are carried out under conditions that are representative for the plants, typically under normal full-load conditions. Most of the parameters are measured as 1-hour averages except dioxins and UFP. It has been shown that potassium, chlorine and sulphur evaporated from biomass during combustion form significant numbers of UFP by condensational nucleation. The emissions of UFP depend on the formation as well as the performance of the flue gas cleaning system.
